libsodium/test/default/box7.c

#include <stdio.h>

#define TEST_NAME "box7"
#include "cmptest.h"

unsigned char alicesk[crypto_box_SECRETKEYBYTES];
unsigned char alicepk[crypto_box_PUBLICKEYBYTES];
unsigned char bobsk[crypto_box_SECRETKEYBYTES];
unsigned char bobpk[crypto_box_PUBLICKEYBYTES];
unsigned char n[crypto_box_NONCEBYTES];
unsigned char m[10000];
unsigned char c[10000];
unsigned char m2[10000];

int main(void)
{
  size_t mlen;
  size_t i;

  for (mlen = 0;mlen < 1000 && mlen + crypto_box_ZEROBYTES < sizeof m;++mlen) {
    crypto_box_keypair(alicepk,alicesk);
    crypto_box_keypair(bobpk,bobsk);
    randombytes(n,crypto_box_NONCEBYTES);
    randombytes(m + crypto_box_ZEROBYTES,mlen);
    crypto_box(c,m,mlen + crypto_box_ZEROBYTES,n,bobpk,alicesk);
    if (crypto_box_open(m2,c,mlen + crypto_box_ZEROBYTES,n,alicepk,bobsk) == 0) {
      for (i = 0;i < mlen + crypto_box_ZEROBYTES;++i)
        if (m2[i] != m[i]) {
          printf("bad decryption\n");
          break;
        }
    } else {
      printf("ciphertext fails verification\n");
    }
  }
  return 0;
}